1. Technical Field
The present invention relates to a method of manufacturing a strip tape for forming a container in which a liquid food such as juice or milk is filled in, and to a strip tape for a container.
2. Background Art
Packaging containers for drinks and fluid food such as milk, juice, and mineral water are obtained from packaging laminated materials such as a web-formed packaging material made from a laminated body of a fibrous base material (such as paper) and a thermoplastic material layer with a decorative design printed thereon and also a crease provided thereon. A strip tape for protection of a container wall edge surface in a sealed section, in which container walls of the container are overlaid on each other, is adhered on an inner side edge portion of the web-formed packaging laminated material, the web-formed packaging laminated material is formed into a tubular form by sealing the web-formed packaging laminated material with a strip tape in the longitudinal direction, a food is filled in the tubular-formed packaging material, the tubular-formed material is sealed in the lateral direction and is formed into pillow-like primary formations, the pillow-like formations are cut into independent pieces, and then the pillow-like formation is folded along a crease to be formed into the final form. The final form includes, a brick-like form, an octangular column, a regular tetrahedron, and the like.
FIG. 2 is a perspective view illustrating an example of a container with a partial cross-section shown in the enlarged state.
In this container 1, on a rear side face of the container (not shown) and a bottom surface of the container (not shown), a vertical seal section 3, in which wall surfaces of the container are overlaid on each other, is formed.
In the vertical seal section 3, packaging materials 4 are overlaid on each other to form a seal as shown in the partial enlarged cross-sectional view. On an inner end face 5 of the vertical seal section 3, both edge portions of a strip tape 6 are adhered to the packaging materials respectively to form a seal covering the end faces 5.
When a fluid food is filled in the container, there is the possibility that a liquid-permeable fibrous material layer of the packaging material such as paper is exposed from the end face and the liquid comes into inside of the container, but since the edge faces are covered with a water-proof strip tale 6, so that it is possible to prevent the liquid from coming into the container. The strip tape is generally made of thermoplastic resin such as low density polyethylene or the like (Refer to Patent document 1).
When the barrier properties is required for a container, the strip tape has a barrier layer in addition to inner and outer layers made of thermoplastic resin such as low density polyethylene.
Materials, which can be used to form the barrier layer, includes, but not limited to, polyester film, ethylene-vinyl alcohol copolymer (EVOH), polychloride vinyliden (PVDC), polyvinyl alcohol (PVA), MXD (methylxylene diamine), aluminum foil, aluminum-deposited film, and transparent deposited film prepared by depositing, in place of aluminum, vapor of (SiOX) or alumina (Al2O3).
Patent document 1: Japanese Patent Laid-Open Publication No. 2001-354916